If you are really poor, it costs nothing. If you have limited means, you pay as much of the fee as you can. If you have means, you pay the full tribunal fee which ranges from $500 to $1,000 depending on the complexity of the case. E.g. if they have to collect documents or depositions from people in another country.
I read that Catholic marriage tribunals in the U.S. ended up $14,000,000 in the red last year. It is not now and never was a money-making proposition. Tribunal fees are minimal compared to civil divorce fees.
I mean this "I demand to have Eucharist" in the first place is not Catholic.
If a person is that spiritually immature, I would be inclined to agree any marriage was not licit. When people complain about this issue and I know it can be hurtful especially for the person who did not want the divorce, I ask them have you prayed about this? Have you really prayed about it? Do you know that spiritual communion can be satisfying? Do you know that there are people all over the world who can not receive for various reasons. Some only see a priest once a month etc.